Asphaltic compositions

ABSTRACT

ASPHALTIC COMPOSITIONS COMPRISING ADMIXTURES OF ASPHALTENES AND HIGH BOILING ESTER PLASTICIZERS, E.G., DIISODECYL PHTHALATES, HAVE THE UNUSUAL COMBINATION OF PROPERTIES INCLUDING EXCELLENT TEMPERATURE SUSCEPTIBILITY, HIGH VISCOISTY AND GOOD RESISTANCE TO AGING AND HARDENING.

United States Patent 3,594,202 ASPHALTIC COMPOSITIONS Luke W. Corbett, Mountainside, and Robert E. Swarbrick,

Belle Mead, N.J., assignors to Esso Research and Engineering Company No Drawing. Filed May 17, 1966, Ser. No. 550,644 Int. Cl. C08h 13/00, 17/22 U.S. Cl. 106278 13 Claims ABSTRACT OF THE DISCLOSURE Asphaltic compositions comprising admixtures of asphaltenes and high boiling ester plasticizers, e.g., diisodecyl phthalates, have the unusual combination of properties including excellent temperature susceptibility, high viscosity and good resistance to aging and hardenmg.

This invention relates to improved asphaltic compositions and the preparation thereof, and more particularly to asphaltic compositions having the unusual combination of properties including excellent temperature suscepti bility, high viscosity and good resistance to aging and hardening. The invention especially relates to asphaltic compositions comprising asphaltenes and organic plasticizers.

A number of techniques are known for producing asphalts of varying physical properties from petroleum crudes. These include straight reduction, steam distillation, vacuum flashing, air blowing, and blending. Blended asphalts are frequently prepared by (a) blending residua from two or more crudes, (b) blending hard and soft residua to obtain intermediate consistencies, (c) blending hard residua with less volatile cutter stocks, (d) blending crude residua with propane precipitated asphalts, (e) blending extraneously obtained asphaltenes with asphalt and (f) other combinations of the foregoing.

In general, the asphaltic compositions obtained by conventional processing methods do not have the combination of properties which are afforded by the compositions of this invention. For example, the hardness of a straight run asphalt may be greatly increased by extensive steam or vacuum distillation of the asphalt, but the resulting product in this instance is generally more susceptible to temperature changes. The air blowing technique, in comparison with the vacuum distillation method, is capable of producing an asphaltic product having improved temperature susceptibility characteristics but which is deficient in other properties such as ductility and aggregate adhesion. Similarly, the blending technique has heretofore produced asphaltic compositions which are deficient in one or more of the properties recited above.

The principal objective of this invention is to provide asphaltic compositions having unusual properties; in particular, asphalts having very good temperature susceptibility coupled with high viscosity and good resistance to aging and hardening. Applications in which this unusual combination of characteristics is particularly desirable include the construction of canal linings and built-up roofs by the lamination of saturated felts with hot asphalt; the manufacture of asphalt shingles, roll roofing, siding, laminated papers and fabrics, insulation backing, asphalt tile and similar materials; and the preparation of culking compounds, electrical insulating materials, water-proofing compounds, rubberized compositions and other formulations.

The present invention provides a class of new and improved asphaltic compositions which are not subject to many of the limitations and disadvantages of petroleum asphalts which have been available heretofore. In accord- H CE ance with the invention, it has now been discovered that asphaltic compositions comprising asphaltenes and conventional organic plasticizers have unusual properties that make them highly desirable in many asphalt applications.

The asphaltenes are the highly aromatic, high molecular weight constituents contained in most petroleum residuum and especially in an asphalt-bearing residua. Typical properties of these materials are well-known in the art, e.g., U.S. Pat. 3,093,573 which is incorporated herein by reference. Asphaltenes are generally prepared by contacting an asphalt-bearing residuum with a precipitant, e.g., a -C C n-parafiin, which causes the asphaltenes to precipitate out as solids and by subsequently removing these solids by filtration or centrifugation, preferably the latter. A fuller desicrption of a method for recovering asphaltenes is given in U.S. Pat. 3,087,887 which is incorporated herein by reference. Nonlimiting examples of residua suitably employed to produce these asphaltenes are derived from Lagunillas, Tia Juana, Boscan, Aramco, Talco, Kuwait, Oregon Basin, Lloydminister, Santa Maria, Kern River and Eucutta crudes. A typical material of the kind described above is a Lagunillas asphaltene fraction having the properties shown in the following table.

TABLE I General characterization of Lagunillas asphaltenes Elemental analysis: Wt. percent Carbon 84.68 Hydrogen 8.71 Sulfur 3.85

Nitrogen 1.24 Oxygen 1.26 Metals (Ni, V, Fe) 0.23

Densimetric analysis:

Molecular weight 3390 Density 20/4 1.092 Percent aromatic carbon 49 Condensation index .29 Number carbon atoms 239 Number aromatic carbons 116 Number rings, aromatic 28.6 Number rings, naphthenic 6.8

1 Analytical Chemistry 36, 1967-1971 (1964:).

The organic plasticizers which are effective to attain the objectives of the invention include the nonvolatile organic liquids which are commonly used to plasticize and soften synthetic vinyl resins such as, for example, polyvinyl chloride. In general, these materials have a COC flash point above 350 F., preferably above 400 F., and may comprise, for example, the C -C aliphatic and aromatic alcohol esters of a C C dibasic acid such as phthalic acid, adipic acid, sebacic acid, succinic acid, pimalic acid, and the like. Other plastisizers well-known and useful herein include the C -C alcohol esters of phosphoric acid, preferably the aryl phosphate esters. It is especially preferred, however, that the plasticized be an ester of phthalic acid with a C C aliphatic monohydric alcohol and mixtures thereof. Specific examples of suitably employed plasticizers include di-n-butyl phthalate, di-n-hexyl phthalate, di-Z-ethylhexyl phthalate, diisooctyl phthalate, di-n-decyl phthalate, diisodecyl phthalate, di-n-dodecyl phthalate, ditridecyl phthalate, diphenyl phthalate, di(n-octy1, n-decyl) phthalate, oxo-bottom phthalate (C l-mixed alcohols), tricresyl phosphate, triphenyl phosphate, diisooctyl adipate, diisodecyl adipate, diisooctyl sebacate, diisodecyl sebacate, and the like.

The blending of the components of the present invention is carried out under conditions such that the solid asphaltenes and the organic plasticizers are combined to form a homogeneous mass. In most cases, it will be 3 4 necessary to admix these materials at a temperature within From the data in Table II, the marked superiority of the range of between about 300 and about 400 F. the asphaltene-plasticizer blends is readily apparent. In Temperatures below about 200 F. are generally not other words, compared to conventional asphalts, the assuflicient to promote fusion of the ingredients while temphaltic compositions of this invention have a higher level peratures above about 450 F. are unnecessary. Temr 5 of temperature susceptibility (penetration ratio), a higher peratures between about 350 F. and about 400 F. have viscosity (Furol Viscosity at 275 F.) and improved rebeen found to be most effective and are therefore presistance to aging and hardening (TFR, percent original ferred. Blending can be accomplished by admixing the penetration). materials in a number of various mixing devices. Specific EXAMPLE 2 examples of suitable mixing devices include a paddle mill, A hOHniX as halt avin was prepared by admixing the an i f i a Spiral blade mlxer a the The 90 penetration diiso ctyl phthalate-asphaltene composiadmlxmg tune i range from a few mmutes to an hou.r tion from Example 1 with 93.5 wt. percent of a mineral 0} dependmg upon the temperatuie. the F aggregate meeting the New Jersey Highway Department to blended and the type of admlxmg equlpment standard specification for surface pavement courses and employed identified as FABC1 (Fine Aggregate Bituminous Con- Broadly this mventlon comprises 10m about 40 to crete). Similarly, the 90* penetration Lagunillas, Veneabout 80 wt. percent of asphaltenes and from about Zuena binder of Example 1 was admixed with 935 Wt.

to about 60 wt. percent of an organic plasticized. A preferred composition, however, comprises from about 45 to about 70 wt. percent of asphaltenes and from about 30 to about 55 wt. percent organic plasticized. For example, a composition comprising from about 45 to about TABLE III.-MARSHALL TEST METHOD 1 55 wt. percent of asphaltenes and from about 45 to about Typical 55 wt. percent organic plasticized has been found to be Aswan? figg fgg especially effective as a hot-mix pavlng binder. DIOP Lagnuillas asphalt, Th admixture as asphaltenes and the Organic l i Marshall briquet properties binder binder paving cizer is found compatible with other materials commonly Stability at 140 F., lbs 2,340 1, 600 750+ used in asphalt compositions and may be blended success- 9 at 16 13 1 oids, vol. percent 3. 4 3. 5 2 5 fully with various amounts of materials such as asbestos, rubber, and mineral fillers. Mineral aggregate (e.-g., stone, ASTM D 1559-62T- sand, and mineral dust) can be admixed with minor It is readily seen from the above data that the asphalamounts of the components of this invention to yield a tic compositions of this invention function as effective hot-mix asphalt paving. For example, a hot-mix asphalt asphalt paving binders. paving composition comprises from about 4 to about 10 Wt. percent, preferably 5 to 8 wt. percent, of the afore- 3 EXAMPLE 3 described asphaltene-plasticizer hot-mix paving binder As to industrial asphalts such as under the Federal and from about 90 to about 96 wt. percent mineral Supp y Catalogue Covering the Pumhilse of aggregate, preferably 92 to 95 wt. percent. Specific exphalt for built-up roofing, water-proofing and damp-proofamples of other materials which may be admixed are ing, Type II, Grade 2, the blended compositions of this asphalt cements, and coal tar cements of suitable coninvention pass those specifications normally made by airsistency. blown asphalts.

The invention can be more fully understood by when Tia Juana asphaltenes were admixed in accordance with ence to the following examples. this invention with diisooctyl phthalate to produce an asphalt composition consisting of 41 wt. percent DIOP and EXAMPLE 1 45 59 wt. percent of said asphaltenes. This composition is compared below in Table IV with a conventional airblown asphalt made from a Tia Juana, Venezuelan crude. It will be noted that the asphaltene-DIOP blend in all respects compare favorably with'the conventional material and the Federal Specification.

This example illustrates the superior properties of asphaltic compositions prepared in accordance with this invention.

Asphaltenes and a conventional vinyl resin plasticizer, i.e., diisooctyl phthalate, were admixed to produce the compositions defined and compared below in Table II. TABLE IV The asphaltenes used herem were the S0lld precipitate I Asphaltene Aipblown Federal recovered from the admlsture of 15 parts by volume of A msp ctmn DIOP asphalts spec. normal heptane and one part of Lagunillas flux residuum. S ft i point a F 173 173 165490 The high quality and utllrty of these asphaltene-plasticizer Penetration at 77: F 29 25 20-50 compositions are demonstrated in the following comgt gaf 22 g 381' parisons (Table II) with asphalt paving binders from D qti lity at 77 1 4.5 5.5 4+ Lagunillas and Elk Basin crude sources, each of which at 325 Q5 have been used for many years in the manufacture of specification paving binders. These two asphalts were EXAMPLE 4 prepared by straight reduction of the aforementioned That blending of asphaltenes with diisooctyl phthalate crudes under vacuum distlllation conditions. yields a product similar to that obtained by blending as- TABLE II Asphalgoelne-glasticizer A h It en 5 sp a from Asphalt from ASTM Lagunillas, Elk Basin,

Proper ties method Venezuela crude Wyoming crude Penetration at 77 F D5-61 74 15s 4 Penetration ratio 39.2/77 101 326 3 ,3 32 Furo1v1s.at275 D88-56 744 505 334 272 17s 126 147 98 Tin film resldue, percent or D1754'63T 86 86 65 64 01 60 59 57 1 48 wt. percent asphaltenes and 52 wt. percent diisooctyl phthalate. 3 40 wt. percent asphaltenes and 60 wt. percent diisooctyl phthalate.

2 45 wt. percent asphaltenes and 55 wt. percent diisooctyl phthalate.

TABLE V.ASTM INSPECTION Asphaltene- Asphaltene- DIOP blends DIDP blends Amount of plasticizer, wt. percent 40 52 55 40 50 55 Penetration at 77 F 27 74 90 25 70 191 Penetration 39.2/77 107 101 99 112 100 100 Soltening pt., F 187 158 130 190 154 134 Thin film res, percent orig 86 86 88 87 It is not intended that this invention be limited to the specific examples presented by way of illustration. The scope of the invention is limited only by the appended claims.

What is claimed is:

1. A composition consisting essentially of from about 40 to about 80 wt. percent of asphaltenes and from about 20 ot about 60 wt. percent of an ester having a flash point above about 350 F. and being prepared from a C C alcohol with a C -C dibasic acid or phosphoric acid, said composition having greater resistance to hardening or aging, and better temperature susceptibility properties, than a conventional petroleum asphalt of the same ASTM penetration value.

2. A composition according to claim 1 wherein said plasticizer comprises an ester of a C -C dibasic acid with a C ,C alcohol.

3. A composition according to claim 2 wherein said dibasic acid is phthalic acid.

4. A composition according to claim 3 wherein said alcohol is a -0 aliphatic monohydric alcohol.

5. A composition according to claim 1 wherein said asphaltenes are present in a concentration Within the range between and wt. percent and said plasticizer is present in a concentration within the range between 40 and 55 wt. percent.

6. A composition according to claim 5 wherein said plasticizer is an ester of phthalic acid with a C C aliphatic monohydric alcohol.

7. A composition according to claim 6 wherein said ester is diisooctyl phthalate.

8. A composition according to claim 6 wherein said ester is diisodecyl phthalate.

9. A composition according to claim 1 wherein said plasticizer comprises an ester of adipic acid with a C C alcohol.

10. A composition according to claim 1 wherein said plasticizer comprises an ester of sebacic acid with a C C alcohol.

11. A composition according to claim 1 wherein said plasticizer is an aryl phosphate ester of a C -C alcohol.

12. A composition according to claim 11 wherein said phosphate is tricresyl phosphate.

13. A hot-mix asphalt paving composition comprising from about 4 to about 10 wt. percent of the composition of claim 6 and from about to about 96 wt. percent of a mineral aggregate.

References Cited UNITED STATES PATENTS 2,693,425 11/1954 Hardman 106273 2,862,869 12/1958 Illman 20823X 2,870,080 1/1959 Illman et a1. 208-23 2,877,129 3/1959 Hardman l06279 2,909,441 10/1959' Pickell l06278X 3,035,930 5/1962 Talley 106273 JULIUS FROME, Primary Examiner I. B. EVANS, Assistant Examiner US. Cl. 208-23 

